The invention relates to apparatus for viewing or recording transparencies such as microfilm, microfiche, still and motion pictures as well as images produced by a television or microscope.
In most microfiche systems the photographed image is reduced in size 24 times or more. In order to be viewed it should be magnified at least half that number to be intelligible to the viewer. One problem in making viewers for such microfiche transparencies which are portable is in "folding" the long optical path necessary to develop this magnification factor of 12 or more. Many prior art devices have used mirrors, lenses and dovetail prism systems in order to accomplish this result. Such devices suffer from a number of disadvantages such as being delicate, expensive, bulky and difficult to operate.